Programmable motion effects

ABSTRACT

Although animation is one of the most compelling aspects of computer graphics, the possibilities for depicting the movement that make dynamic scenes so exciting remain limited for both still images and animations. In our work, we experiment with motion depiction as a first-class entity within the rendering process. We extend the concept of a surface shader, which is evaluated on an infinitesimal portion of an object's surface at one instant in time, to that of a programmable motion effect, which is evaluated with global knowledge about all portions of an object's surface that pass in front of a pixel during an arbitrary long sequence of time. With this added information, our programmable motion effects can decide to color pixels long after (or long before) an object has passed in front of them. In order to compute the input required by the motion effects, we propose a 4D data structure that aggregates an object's movement into a single geometric representation by sampling an object's position at different time instances and connecting corresponding edges in two adjacent samples with a bilinear patch. We present example motion effects for various styles of speed lines, multiple stroboscopic images, temporal offsetting, and photorealistic and stylized blurring on both simple and production examples.

References

1. Agarwala, A., Dontcheva, M., Agrawala, M., Drucker, S., Colburn, A., Curless, B., Salesin, D., and Cohen, M. 2004. Interactive digital photomontage. ACM Trans. Graph. 23, 3.
2. Assa, J., Caspi, Y., and Cohen-Or, D. 2005. Action synopsis: pose selection and illustration. ACM Trans. Graph. 24, 3.
3. Autodesk. 2010. Autodesk Maya 2010. http://www.autodesk.com/maya.
4. Bennett, E. P., and McMillan, L. 2007. Computational time-lapse video. ACM Trans. Graph. 26, 3.
5. Bouvier-Zappa, S., Ostromoukhov, V., and Poulin, P. 2007. Motion cues for illustration of skeletal motion capture data. In Non-Photorealistic Animation and Rendering 2007.
6. Burr, D. C., and Ross, J. 2002. Direct evidence that "speedlines" influence motion mechanisms. Journal of Neuroscience 22, 19.
7. Catmull, E. 1978. A hidden-surface algorithm with anti-aliasing. SIGGRAPH Comput. Graph. 12, 3.
8. Chenney, S., Pingel, M., Iverson, R., and Szymanski, M. 2002. Simulating cartoon style animation. In NPAR '02: Proceedings of the 2nd international symposium on Non-photorealistic animation and rendering.
9. Collomosse, J. P., Rowntree, D., and Hall, P. M. 2005. Rendering cartoon-style motion cues in post-production video. Graph. Models 67, 6.
10. Cook, R. L., Porter, T., and Carpenter, L. 1984. Distributed ray tracing. SIGGRAPH Comput. Graph. 18, 3.
11. Cook, R. L., Carpenter, L., and Catmull, E. 1987. The reyes image rendering architecture. SIGGRAPH Comput. Graph. 21, 4.
12. Cutting, J. E. 2002. Representing motion in a static image: constraints and parallels in art, science, and popular culture. Perception 31, 10.
13. Fóris, T., Márton, G., and Szirmay-Kalos, L. 1996. Ray shooting in logarithmic time. In WSCG'96 - 4-th International Conference in Central Europe on Computer Graphics and Visualization'96.
14. Goldberg, E. 2008. Character Animation Crash Course! Silman-James Press.
15. Goldman, D. B., Curless, B., Salesin, D., and Seitz, S. M. 2006. Schematic storyboarding for video visualization and editing. ACM Trans. Graph. 25, 3.
16. Grant, C. W. 1985. Integrated analytic spatial and temporal antialiasing for polyhedra in 4-space. SIGGRAPH Comput. Graph. 19, 3.
17. Haller, M., Hanl, C., and Diephuis, J. 2004. Non-photorealistic rendering techniques for motion in computer games. Comput. Entertain. 2, 4.
18. Hanrahan, P., and Lawson, J. 1990. A language for shading and lighting calculations. SIGGRAPH Comput. Graph. 24, 4.
19. Hsu, S. C., and Lee, I. H. H. 1994. Drawing and animation using skeletal strokes. Proceedings of SIGGRAPH 94.
20. Hulten, P., Ed. 1986. Futurism & Futurisms. Abbeville Press.
21. Kawagishi, Y., Hatsuyama, K., and Kondo, K. 2003. Cartoon blur: Non-photorealistic motion blur. Computer Graphics International Conference.
22. Korein, J., and Badler, N. 1983. Temporal anti-aliasing in computer generated animation. SIGGRAPH Comput. Graph. 17, 3.
23. Lake, A., Marshall, C., Harris, M., and Blackstein, M. 2000. Stylized rendering techniques for scalable real-time 3d animation. In NPAR '00: Proceedings of the 1st international symposium on Non-photorealistic animation and rendering.
24. Liu, C., Torralba, A., Freeman, W. T., Durand, F., and Adelson, E. H. 2005. Motion magnification. ACM Trans. Graph. 24, 3.
25. Masuch, M., Schlechtweg, S., and Schulz, R. 1999. Speedlines: depicting motion in motionless pictures. In ACM SIGGRAPH 99 Conference abstracts and applications.
26. McCloud, S. 1993. Understanding Comics. Kitchen Sink Press.
27. Nienhaus, M., and Döllner, J. 2005. Depicting dynamics using principles of visual art and narrations. IEEE Computer Graphics and Applications 25, 3.
28. Noble, P., and Tang, W. 2007. Automatic expressive deformations for implying and stylizing motion. The Visual Computer 23, 7.
29. Porter, T., and Duff, T. 1984. Compositing digital images. SIGGRAPH Comput. Graph. 18, 3.
30. Potmesil, M., and Chakravarty, I. 1983. Modeling motion blur in computer-generated images. SIGGRAPH Comput. Graph. 17, 3.
31. Ramsey, S. D., Potter, K., and Hansen, C. 2004. Ray bilinear patch intersections. Journal of Graphics, GPU, and Game Tools 9, 3.
32. Sung, K., Pearce, A., and Wang, C. 2002. Spatial-temporal antialiasing. IEEE Transactions on Visualization and Computer Graphics 8, 2.
33. Wang, J., Drucker, S. M., Agrawala, M., and Cohen, M. F. 2006. The cartoon animation filter. ACM Trans. Graph. 25, 3.
34. Whitaker, H., and Halas, J. 2002. Timing for Animation. Focal Press.

Index Terms

• Computing methodologies

  • Computer graphics

    • Animation

    • Image manipulation

    • Rendering